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Major Pacific Battles

In December 1941 Japan attacked the United States at Pearl Harbor, Hawai'i, causing the U.S. to enter World War II. Over two years would pass until the Allies reached their great turning point in the Pacific War: the defeat of the Japanese at Guadalcanal in February 1943. The Japanese were placed on the defensive as the U.S. began taking strategic bases across the central and southwest Pacific. By the summer of 1944, the Americans were nearing Japan. The final year of the war would bring bloodshed and hardship to the U.S. soldiers, sailors and Marines who liberated territory closer and closer to Japan's home island, and take a tremendous toll on Japanese soldiers and civilians as well.

U.S. Marines dig in on the beach at Saipan. Defense Dept. photo (Marine Corps.) June 1944. Library of Congress.

June-July 1944: Saipan
On June 15, 1944, American forces invaded the island of Saipan, part of the Mariana Islands in the Central Pacific. Securing Saipan was of critical importance to the U.S.; its airfields would put the Army Air Force's new B-29 bombers within striking distance of the main Japanese islands. For the Japanese, keeping Saipan was crucial in stopping the American advance.

In what became known as the Battle of the Philippine Sea, American and Japanese carriers fought a two-day sea and air battle off the coast of Saipan. It would go down as one of the biggest carrier battles of World War II. Japan lost three aircraft carriers and more than 300 planes. On Saipan, the Marines and army faced an enemy well dug-in and prepared to fight to the death. Of the 30,000 Japanese troops who defended Saipan, less than 1,000 remained alive when the battle ended July 9.

However, it was the civilian casualties that stunned American troops. As the battle came to an end, large numbers of civilians committed suicide, terrified of being captured by American forces. Japanese government officials exploited the suicides at Saipan to their advantage, calling those who took their lives heroes and encouraging the entire Japanese population to follow suit if the time came. Death before surrender had been the national policy for Japan's servicemen; now it became the national policy for civilians as well.

October-December 1944: Leyte
In October 1944, General Douglas MacArthur and his Sixth Army returned to the Phillipines by way of the island of Leyte. More than two and a half years had passed since MacArthur had reluctantly abandoned his troops in the Philippines, retreating to Australia, where he had vowed, "I shall return." After he waded ashore MacArthur delivered his famous "I have returned" speech. Offshore the U.S. Navy and the Imperial Navy waged the largest naval battle in the history of warfare. The Battle of Leyte Gulf destroyed the Japanese Navy as an effective fighting force. It was during this battle that U.S. sailors first witnessed the kamikaze attacks that would become commonplace five months later in the battle of Okinawa. As many as sixty-five thousand Japanese soldiers died defending Leyte. More than 15,000 Americans were killed or wounded.

January-March 1945: Philippines Campaign
In early January 1945, the biggest army the U.S. would commit to one battle in the Pacific invaded the main Filippino island of Luzon, defended by 287,000 Japanese. According to historian Donald Miller, this was "the largest army the Americans faced in the Pacific." When organized battle ended after two months, Manila was one of the most thoroughly devastated cities of World War II. The Japanese Navy had blown up Manila's harbor and destroyed the old city. MacArthur's Sixth Army suffered 38,000 individuals killed or wounded. Despite defeat, stalwart Japanese would continue to fight in the jungles and mountains of the Philippines until the very end of the war. Japan lost a total of 400,000 lives in the Philippines.

February-March 1945: Iwo Jima
On February 19, 1945, American forces invaded the tiny island of Iwo Jima to secure airstrips for American B-29 flyers. They encountered 21,000 well-entrenched Japanese defenders. It would take the Marines over a month of fighting over an inhospitable terrain to dig out and overtake the Japanese. When the battle ended on March 26, 1945, as many as 7,000 Americans were dead and 24,000 wounded. Almost 6,000 of those killed were U.S. Marines. Only 1,038 of the 21,000 Japanese defenders were captured alive. To the B-29 crewmen who would subsequently use Iwo Jima as a safe haven during their 3,000-mile bombing runs to Japan, gratitude to the Marines would be immeasurable.

April-June 1945: Okinawa
By April 1945, the war in Europe had ended with Allied victory, but the Pacific theater was yet to see its deadliest days. The final land battle of World War II took place a mere 350 miles from the main islands of Japan. The U.S. planned that Okinawa, once captured, would serve as a staging area for an invasion of the main islands.

Okinawa saw 82 days of brutal warfare in horrific conditions at places like Kakazu Ridge, Sugar Loaf Hill and Kunishi Ridge. U.S. Marines and Army troops fought a bloody battle of attrition against an enemy concealed in intricate underground defense systems. When the island was finally secured, more than 12,000 U.S. soldiers and Navy personnel were dead or missing and more than 36,000 were wounded. Seventy thousand soldiers of the Japanese 32nd Army died on Okinawa, joined by as many as 100,000 to 150,000 civilians trapped in the crossfire.

The War's Final Weeks
The bloodbath at Okinawa was a major factor in President Harry Truman's decision-making about an invasion of the Japanese home islands. Would the Japanese never capitulate? How many more Americans would die before the war could end? The events of summer 1945 — including the use of two atomic bombs on the Japanese cities of Hiroshima and Nagasaki -- brought the war to a close before another land battle could take place.

The Japanese surrender on August 14 spared the American soldiers who survived Okinawa — and hundreds of thousands of others — from having to invade Japan and face high odds of becoming casualties. It also spared untold numbers of Japanese soldiers and civilians.